2x^2(x^3-3)=6(81-x^2)

Question

2x^2(x^3-3)=6(81-x^2)

Answer 1

(x - 9)^2 = (x - 3)^2 
x^2 - 18x + 81 = x^2 - 6x + 9 
- 18x + 81 = - 6x + 9
- 18x + 6x = 9 - 81 
- 12x = - 72
x = 6

Ответ
6